A Clockwork Nightmare
by PrimadonnaGurl13
Summary: Victorian London, 1878, and the Shadowhunters are recovering from their ghastly attack with Mortmain & his automatons. Thankfully, he's dead & so are his creations. The London Institute is at peace once again. Or so they think. Upon an outing, Tessa and Cecily come across some rather unexpected visitors. AU
1. Prologue

**I have to big-up my writing partner in crime, The Pale Red Queen, for writing this prologue, and myself for coming up with the crossover. We both hope you enjoy this, and there's lots more to come. Hopefully. **

**P.S. "big up" is British slang for "congratulate" "give credit to" "bow to her greatness" ^_^**

**PROLOGUE**

December 1878

Tessa Gray quietly walked down the stone halls of the London Institute. The last few months had been a jumble to her. Mortmain was dead and gone. So were his clockwork creations. She should be happy. Her worst enemy would never bother her again, and she could live her life in serenity.

But no. She had to complicate the situation between her, Will, and Jem. After she was kidnapped, everyone thought that Jem was dead. However, after the battle at Cadair Idris, they were able to grab ahold of Mortmain's extra yin fen and give it to Jem; enough to sustain him at least for another year. And of course there was that which transpired between Will and Tessa in the cave. Jem was fully aware of Will's feelings for Tessa and her's for his. Jem then cancelled the engagement, for the sake of both his parabatai and for her. Tessa just hated being stuck in this messy love business. The three of them agreed just to be friends, although Tessa was sad to see the distance between all of them.

Tessa finally made it to her destination: the library. It was the perfect spot to escape away from her real life, her personal refuge. Although, Will also loved books as much as Tessa did, though he spent most of his reading in his room. Tessa went automatically towards the only shelf that contained English books and pulled out Wuthering Heights. She sat down comfortably on an armchair in front of the fire and lost herself in the book. She did not even hear the great wooden door open then close and the bustling of skirts that followed. A shadow loomed over her and Tessa looked up.

"Charlotte!" Tessa exclaimed, surprised. The older woman stood looking down at Tessa, although it was hard to read the expression on her face. Her belly was getting evermore bigger, as she and Henry were expecting their little "Buford" in the next couple months.

"Sorry to surprise you Tessa," Charlotte said apologetically, giving Tessa a small smile, "but could you join us in the drawing room? Henry, Gideon, Gabriel, Cecily, Will, Jem, and Sophie are all there and we would appreciate it if you came too. There is someone I would like you all to meet."

Tessa nodded and followed Charlotte out of the library and towards the drawing room. She pondered over who it possibly could. Maybe another Shadowhunter coming to join them in training? Tessa really did not know. They reached the drawing room, where all the other Shadowhunters were already sitting, although none of them were talking to each other. Will was leaning against the fireplace, as usual, with his arms crossed and a stubborn look across his handsome face. Jem was seated nearby in a chair, his cane resting next to him. His silver features were still pronounced, but he looked calmer and healthier than before, ever since getting the extra dose of yin fen. Everyone else was seated in either chairs or couches such that it formed a ring around a single chair. And someone was seated in that chair.

A girl. Or rather, it was a woman that Tessa had never seen before. She seemed to be much shorter than Tessa was, and rather petite like Charlotte. She was wearing a maid's outfit, like one that Sophie used to wear before she had chosen to Ascend. Her skin tone was a shade darker, almost as if it had been tanned, and she had dark brown hair swept up into a neat bun. Her big, brown eyes were wide and were looking at everyone curiously. She was very pretty, Tessa decided.

Everyone else in the room, including the maid, looked up as Charlotte and Tessa entered the room. "Oh good, everyone is here," Charlotte commented, "I would like you all to meet Oswin Oswald. Oswin, that over there is William Herondale. Next to him is James Carstairs. Then there's Cecily Herondale, Gideon and Gabriel Lightwood, and Sophie Collins. You've already met my husband, Henry. Oh, and next to me is Tessa Gray." Tessa gave the other girl a smile, and Oswin returned it with a grin.

"As you all know, since Sophie has begun to Ascend, we have been one short of a maid," Charlotte continued, "luckily, Oswin here has the Sight and happily obliged to work for us here at the Institute."

"I would love to get to know all of you," Oswin said warmly, speaking rather rapidly.

"As would we," Charlotte said honestly, "now, I want all of you to be on your best behavior," she looked directly at Will when she said this, "we want Oswin to feel like family here."

Will rolled his eyes.

Oswin had in fact easily transitioned into the Institute. Better than everyone expected. She often joined them for meals and proved to be make the atmosphere a lot lighter by throwing witty and fun jokes in. Everyone loved her, and indeed she was enjoying her time at the Institute. It seemed to have taken a load off Charlotte, who was busy with her duties as both the head of the Institute and as Consul.

Oswin had been at the Institute for three weeks when Charlotte came to Tessa, who as usual was in the library. The Christmas ball was coming up in just two days and there was a lot of preparation going on.

"Tessa, would you mind if you would go out with Cecily to run some errands for the party? I need all the help possible before the big day," Charlotte said.

"Of course I'll help," Tessa said sweetly. She owed Charlotte so much, and helping her with errands was just a minor duty.

"Oh good," Charlotte seemed relieved and her shoulders relaxed, "I've already asked Cecily and she agreed. She's waiting for you at the entrance."

Tessa then hurried to her room. Since Sophie was no longer her maid, it was Oswin who would usually help her dress. Unfortunately, Oswin was also preparing for the ball and was extremely busy with that. So Tessa would have to do it alone. She hated being so dependent on others for this. She felt so spoiled being at the Institute.

Tessa grabbed her cloak, gloves, and hat and put them on. She hurried downstairs and Cecily was indeed waiting for her. Even though Cecily had been at the Institute for nearly five months, Tessa still was shocked by how much she resembled her older brother. Tessa had no idea how long it would take before she got accustomed to their striking similarities. Not to mention that the light blue cloak and hat Cecily wore made her midnight blue eyes stand out even more. She was radiant.

"Hello there Tessa," Cecily greeted her, "ready for our little adventure?"  
"Ready as I would ever be," Tessa said, laughing. She pushed open the door to the Institute and the two girls made their way out. The snow was falling hard and painting a clean layer of white across the cobblestone streets in front of the Institute.

"So," Cecily said, pulling out a wrinkled sheet of paper from her breast pocket, "it looks like Charlotte wants us to go buy some wreaths just a couple streets away." She folded away the paper and led the way.

As they turned the corner away from the Institute, they stumbled into something big in front of them. Not only was it big, but also made of metal. And it was staring right at them. An automaton.

Tessa and Cecily both let out a scream.


	2. Chapter 1

**Thank you so much for the reviews and hits already. Myself and The Pale Red Queen are taking turns on chapters, so this time, dun dun duuun - it's my turn. And it's from the Doctor's POV. Enjoy. :)**

**Chapter 1**

He shouldn't have gone. He should have just...he didn't know. Gone to Mars or somewhere far far away from here. How had he ended up in Victorian London _again_?! It was unexplainable. Clearly the TARDIS knew something he didn't. There had to be reason. There just had to be.

The Doctor stormed back into the TARDIS away from the smoky streets of London. Seconds later, the same girl he'd come across, followed him. He wanted to tell her to leave, but he didn't have the heart. That made him chuckle. _Heart_. He had two of them and still he didn't know how to control even one.

The girl, who hadn't yet introduced herself, looked at the Doctor with intense curiosity. "You dress most strangely," she said, her accent a mix of American and English. She had an innocence about her but he still felt offended.

"No," he said. "you dress strangely. I dress magnificently." The Doctor grinned proudly and straightened his bow tie with both hands as though he were preparing to present himself. He did like to impress. But perhaps he should have dressed properly for the era. His casual cream shirt and suspenders, the bowtie, the tweed jacket were probably a bit too modern for this poor girl to comprehend. He patted his hair. The hat. He'd forgotten a hat. Most men in this time wore hats, didn't they? He liked hats. They were cool.

Quickly he turned back to the TARDIS console, his face suddenly void of humour. Panic soared through him. How had he gotten into this? He'd left Clara at home as she'd requested. He traveled alone for a change. Maybe engage in some human interaction wherever he landed, despite him finding humans wonderfully strange creatures. Then again, he supposed he was already talking to a human-

A sudden thought flitted through his brain. Spinning on his heels he marched up to the girl now standing hesitantly on the steps, looking up at him with wide wondering gray eyes. She seemed so unsure. The Doctor whipped his sonic screwdriver out of his inside jacket pocket and scanned her. He studied the results carefully then frowned.

Sharply he said, "Who are you? Or more to the point, what are you? You're not human. I want to know who or what you are, why have you come here?" His demands appeared to have scared the poor girl and he changed his tactic. "I don't appreciate non humans sneaking up on me. It's rude."

She backed away as he came closer to her almost inches away. He didn't like tricksters. And anyone not human, unless it was himself, or allies, were usually bad.

"M-my name is Tessa Gray, sir." The Doctor waited, brow creased In intense thought. His head hurt from it. "I am a Shadowhunter. Or some form of one." This startled him.

"A what? Shadowhunter? Ridiculous. Those, whatever that is, don't exist. Never heard of such a thing. It sounds disgusting." He made a noise with his mouth, as though he'd tasted something bad. "You can't possibly hunt shadows. No, I'll tell you what you are. You are a sneaking little evil-"

"Sir, please. You appeared out of nowhere when myself and my... companion needed to be saved. Those...monsters. They belong to a man named Mortmain, but he died. So..." This Tessa girl blinked fast. Tears formed in her eyes and the Doctor, not liking it when anyone cried, quickly backed up to the console and began pressing buttons. He had a thing about pressing buttons.

"Monsters, you say? Well, they are that. Who is this...Mortmainy person? I've never heard of him. I don't like the letter M. They always belong to mean things. You know, I've dealt with mean things before. A lot of them. It does get a bit boring sometimes but oh well." He stopped what he was doing and turned to face the girl. Her expression was one of bewilderment. In a spark of inspiration, he passed her and out of the TARDIS, into the street. The skies were a sparkly dark blue, the sun set long ago, and London smoke lingered around the air.

"What is it?" the girl, Tessa, asked curiously.

"What?" The Doctor spun in a circle, the heels of his shoes squeaking on the pavement. "Oh, wait here," He flitted back into the TARDIS and not a minute later he reappeared in front of the girl wearing the correct attire. She stood open mouthed.

"How did you- What- Sorry, I mean to say, that was very impressive."

The Doctor gave her big smile, happy with the compliment. He fixed his top hat until it was perfectly centre. He wished there was a mirror somewhere. Once that was done, he made a bow gesture to the girl and said, "Hello, I'm the Doctor."

The brown haired girl, whose name escaped him, looked confused. "Doctor who?"

The Doctor pointed a finger at her and winked. "Exactly." A second later he was heading down the street in his new outfit: white shirt and black tie, black jacket, black trousers and shiny shoes. And cane.

**A/N: S****orry it's so short. I hadn't intended for that to be the case, but my writing partner gave the all clear, when I was thinking this was just a random scene. Turns out, it was the chapter. Haha. **


End file.
